The present invention relates to a developer resin which is useful in providing visible images through reaction with a color precursor and which is useful in providing transparencies or in providing reproductions having a glossy finish. It more particularly relates to a developer sheet which is capable of providing a controlled degree of gloss ranging from matte to high gloss.
The developer sheet of the present invention can be used in conjunction with conventional pressure-sensitive or carbonless copy paper, or photosensitive and thermal imaging systems in which visible images are formed by image-wise transferring a color precursor to the developer sheet.
Pressure-sensitive copy paper is well known in the art. It is described in U.S. Pat. Nos. 2,550,446; 2,712,507; 2,703,456; 3,016,308; 3,170,809; 3,455,721; 3,466,184; 3,672,935; 3,955,025; and 3,981,523.
Photosensitive imaging systems employing microencapsulated radiation sensitive compositions are the subject of commonly assigned U.S. Pat. Nos. 4,399,209 and 4,416,966 to The Mead Corporation as well as copending U.S. patent application Ser. No. 320,643 filed Jan. 18, 1982. These imaging systems are characterized in that an imaging sheet, which includes a layer of microcapsules containing a photosensitive composition in the internal phase, is image-wise exposed to actinic radiation. In the most typical embodiments, the photosensitive composition is a photopolymerizable composition including a polyethylenically unsaturated compound and a photoinitiator and is encapsulated with a color precursor. Exposure image-wise hardens the internal phase of the microcapsules. Following exposure, the imaging sheet is subjected to a uniform rupturing force by passing the sheet through the nip between a pair of pressure rollers in contact with a developer sheet whereupon the color precursor is image-wise transferred to the developer sheet where it reacts to form the image.
In applications in which the aforementioned pressure-sensitive and photosensitive imaging systems are used to reproduce graphic or picture images, a high degree of gloss is often desired in the reproduction. Where a transparency is desired, the reproduction must transmit light efficiently. These objectives are difficult to achieve using conventional developers. Commonly assigned U.S. application Ser. No. 905,727 filed Sept. 9, 1986 discloses glossable developers prepared from phenolic resins.